Why Are King Penguin Chicks Brown and Fluffy? Chick Facts

Why king penguin chicks need such a thick coat

Most penguins raise their chicks in a single summer, when food is plentiful. The king penguin cannot, because its chick is so large and grows so slowly. The whole cycle, from egg to independent young bird, takes about 14–16 months. That means every king penguin chick spends the cold, stormy winter months of May to September standing in the open colony.

A newly hatched chick has only a thin covering of down and depends entirely on its parents for warmth. For its first 30–40 days it sits on a parent’s feet, under a warm fold of belly skin called the brood pouch. After that it is too large to fit, and it grows a second, much thicker layer of long, woolly down. This coat traps air close to the body, working like a down jacket, and keeps the chick warm through wind, rain, sleet and snow.

The down has one big drawback: it is not waterproof. A downy chick that fell into the sea would quickly become soaked and chilled, so the young bird must stay ashore until it molts into proper feathers.

Why brown rather than black and white?

The dark brown color of the chick’s down has no single proven explanation. Adult penguins are black and white mainly as camouflage at sea, dark from above and pale from below. Chicks do not swim, so this countershading would give them no benefit on land.

Dark colors absorb more heat from sunlight than pale ones, and some biologists suggest the brown down may help chicks warm up on sunny days, but this has not been firmly established. Whatever its exact purpose, the coat is a temporary uniform. Chicks of the closely related emperor penguin, which grow up on Antarctic sea ice, have silvery-gray down with a black-and-white face instead.

The “woolly penguin” mix-up

Large brown chicks look so different from the sleek, orange-marked adults that they confused early visitors. Many accounts say that 19th-century naturalists and explorers first took them for a different kind of penguin altogether, sometimes nicknamed the woolly penguin. The detail of who made the mistake is not well recorded, but the confusion is easy to understand.

Late in their first year, chicks can be almost as heavy as their parents and look even bigger because of their bulky down. When they molt, the old down comes away in patches, leaving chicks with tufts of brown fluff on their heads or backs and sleek new feathers underneath.

Life in a crèche and the winter fast

From about five or six weeks old, chicks gather in groups called crèches. These can contain hundreds of chicks, watched over by a few adults, and huddling together saves warmth and offers some protection from predators. Meanwhile both parents can go to sea at the same time to catch lanternfish and squid. When a parent returns, it calls, and its own chick answers; parents recognize their chick by voice alone.

By April, at the start of the southern winter, a well-fed chick is almost adult-sized and carries large fat reserves. Then the hard part begins. In winter, food lies farther from the colonies, and parents visit far less often. Chicks may go weeks between meals, and some wait much longer, living on their stored fat and losing a large share of their weight. Feeding becomes regular again in spring, around September, and the chicks quickly regain condition.

Not every chick makes it. Southern giant petrels kill many chicks of all sizes, and skuas take small ones. Chicks from eggs laid late in the season often do not grow large enough before winter, which is one reason king penguin pairs usually succeed in raising young only every other year, or twice in three years.

Molting and going to sea

In late spring and early summer, from about November to January, the chicks molt. Sleek, waterproof juvenile plumage replaces the brown down over a few weeks. Young king penguins then look much like adults, but their ear patches are paler and yellower.

Once the molt is complete, the young birds leave the colony and head out to sea alone, at roughly 10–13 months old. Timing matters: they set off in summer, when food is most abundant, giving them the best chance of learning to hunt. Learn more about adult life in our king penguin profile and about how young birds compare with other species in how long penguins live.

King penguin chick facts at a glance

Chicks are only one part of the king penguin’s unusually long breeding cycle. To see what the same chicks will eat once they reach the ocean, read what penguins eat.